This show bugs me to no end, sometimes.

They get a lot of talking heads, military experts, and such, and it seems that very few of them ever held a rifle, let alone personally shot all 10 on this list. They go on and laud praise or critism on every rifle, capriously, then gush over the AK47.
I have in one form or another own or have owned, or have a friend who owns / owned just about every rifle on this list, except for the StG44 and the Steyr AUG.
1. AK47 / AKM47 / AK74
I don't have a problem with this rifle being number one. I do have a huge problem why they claim it should be number one. This is not a fine rifle. Accuracy is mediocre, at best. Handling is poor. It has all the right pieces in all the wrong places. (I finally learned how to perform the single handed magazine change from the Spetnaz show from Weaponology.

) The rifle is somewhat clumsy. The balance of the gun makes and the odd comb angle of the stock points the natural point of aim lower that your sight picture. The sight radius is just horrible. The ammo is powerful enough, but not particulary accurate. One could reliably hit a man sized target at 200 yards, but we're talking about 10" groups at best.
I've shot a fully automatic version and own a semi-auto civilian version. (It was really cheap back in 1999.) It is fun, easy to use, and the ammo was plentiful and inexpensive. Utterly reliable, and nearly indestructable.
This gun is NOT innovative. The StG44 proved that. If this rifle should be number one, it's because it is idiot proof, and there are probably over 50 million of them out there. It does its job of spitting out lead, and it does it well.
2. M16
I've shot an M16A1 and I own several AR15s in different configurations. I would take this rifle into combat, because I know it and trust it. I'm also of small stature, and I like the low recoil and light weight of this rifle. Are there more reliable rifles out there? Sure, but I take care of mine, and they never have let me down. Stopping power? Yeah, the 5.56x45mm NATO round (M855 / SS109) and the old M193 weren't powerhouse past 250 yards. But at least, I could hit targets that far and much farther out with my rifle. I'm good to 500+ yards on a decent day. CMP shooters can group tight shots at 600 yards with accurized versions of this rifle.
If your target doesn't go down with the first shot, pull the trigger again, and repeat as necessary.
3. Lee Enfield SMLE - No.1 MkIII*, No.4, No.5 Jungle Carbine
This rifle probably should have been number 1.
The final battle rifle of the British Empire, and probably one of the best bolt action rifle designs ever devised. I own a few of them, and never wish to part with them. They have probably the smoothest action in a military rifle. One can easily get off 10 aimed shots in 15 seconds with reasonable accuracy, especially with the slightly heavier No3.
The Jungle Carbine is fun to handle, but a harsh rifle to shoot.
4. M1 Garand
I own one... my friend owns one. His friend owns one. For the time, it was a great battle rifle. If given another 15 years to work on his rifle, John Garand would have probably made an M14 in .30-06... maybe.
5. FN FAL
I want one. I like it. My friend owns one... and sold it to someone else. (Some friend

)
A bit heavy, but it's available in paratrooper configuration with a folding stock. Accuracy is acceptable. - Not as good as the HK G3 / HK91.
6. Mauser Gewehr M1898 / K98k
I own a few, and love them all. I would not feel undergunned taking one of these into battle. They should probably have combined this rifle with the M1903 Springfield. (They combined the F-86 Sabre and the MiG-15 in Top Ten Fighers.) While this rifle wasn't truly innovative, it was the one which brought all of the good ideas together into one package.
7. Steyr AUG / Gewehr 77
Want one. Can't afford them. We don't import them. The new American made knock offs are so expensive. If something should have scored high in innovation, it's this rifle. One receiver can do many jobs with 4 different barrels. Yeah, there are some inherent problems with most bullpup designs, but it looks like Steyr has address the really major ones. The Australians are giving them high marks for their performance in East Timor.
8. Springfield M1903
Own a M1903 and M1903A3, sold a M1903A1.
An American Mauser replacement for the Krag... and a pretty darn good one. However, it was the M1917 Enfield that really carried the U.S. Army in World War I and in the early stages of World War II in the Philippines.
9. Sturm Gewehr StG44
The first true assault rifle. This is a select fire rifle, not a machine gun. I've seen and hear it shoot too. It belongs here just as the AK47, M16, FAL, Steyr, and M14 (before the military removed its select fire capability). Its cyclic rate of fire is no faster than any of those other rifles. In fact, it is only around 550 rounds per minute. The AK47 and M16A1 shoot much faster at 650 and 700+, respectively.
10. M14 (a.k.a. The Garand revised)
I love mine. Don't get me wrong, but I would not take this long, heavy rifle into combat. Huffing this rifle and its ammo would kill me. (Yeah, I am a wuss.)
It's better than the M1 Garand. It's accurate. It hits hard. It's reliable and well-built. It's still in service and doing a job in the Navy, the Marines and in the Army in the sandbox of Iraq and Afghanistan. For an interesting sidenote, check out the Italian BM59. In looks and on paper, it should remind you of something.

Limited service life? That depends on what you call service. High power match shooters only recently in the last decade converted to AR15s.
My list would look more like this:
1. Lee Enfield - Millions made. 2 World Wars and countless battles prior to.
2. AK47 / AK74 - Over 50 million served. - The fast food of battle rifles.
3. M16 - In service for over 40 years and still going strong. Some good, some bad. Gotten a lot better.
4. Mauser M1898 / Kar98k & M1903 Springfield - Wonderful, well made rifles. 2 World Wars and hundreds of battles. The Spanish M1895 in 7mm would probably be the one that really changed history. The Mauser became a world beater, Paul Mauser got rich, and the Americans ditched the Krag and got Springfields.
5. FN FAL & HK G3 (I love my HK91, but it is too heavy. I would be better off with a HK33.)
THe FN FAL was the "right hand of NATO" the HK G3 was purchased by all other NATO countries that didn't get FALs... or made their own rifle.
6. M1 Garand / M14 & SKS & SVT40 - These are all contemporaries. They are 2nd and 3rd generation auto-loading rifles. The Garand being the greatest produced in numbers. The SVT40 wasn't a large production rifle, but I was amazed that it functioned so well, but is more susceptible to dirt and mude than the M1.
The SKS is a good rifle with better accuracy than the AK47, but is limited by its charger loaded 10 round not detachable box magazine.
7. M1917 Enfield
We didn't have enough M1903s when we went to war again Germany in 1917, and we couldn't make enough. We made a bunch of P14s for Great Britain in .303 British. Why not rechamber them for .30-06? Big, heavy, but easy to shoot and well balanced. A long Mauser action that is strong and durable. Springfields get all the glory. Enfields did most of the work.
8. M1891 / M91/31 Mosin Nagant
Not a particular great rifle, but a durable, easily produced rifle that got the job done. Clunky action, and not particularly accurate, although some sniper versions are pretty good.
9. Steyr AUG / Gewehr 77 & FAMAS & L85 / SA80
Bullpups maybe the way of the future. I hope not, but they are cool in their own way. The Chinese and Israelis have their own now too, and these rifles lead the way.
10. M1 Carbine
WHAT?!!! Yeah. The first true rabbit shooter. I know, I know, I know... anemic ammo, blah, blah, blah. But this little carbine set the trend for the PDWs of today, like the FN P90. Remember, it was the M1 Carbines that the USAF wanted to replace with the M16s, that the Army rejected. Over 6.25 million M1 carbines were produced in 4 years of war! That's saying something. I'm not sure what, exactly... but love it or hate it, it found its way into the hearts of many American shooters and gun enthusiasts.
By the way, jumpingrunt. I can't agree with your statement about the .303 British cartridge. It is slow, compared to our .30-06 by about 200 feet per second, but it is a heavier bullet. The same could be said about the 8mm Mauser (7.92x57mm), and that was a very effective man stopper... hundreds of thousand of American, British, Italians, Russians, French, Dutch, Polish, and Greeks can't be wrong.
The British .303 service round was plenty good to kill alot of Boers, Germans, Japanese, and Italians. What did the .45-70 kill besides a lot of buffalo? Spanish? I don't think so. They had 7mm Mausers. And if the Krag was obsolete in the Spanish American War... the black power Trapdoor Springfields were hopelessly outclassed.
The British used .303 in Lewis Guns, Vickers Machineguns, Browning Machineguns in their Hurrcanes, Spitfires, and of course it was also in their Bren LMGs. As far as weight of the Lee Enfield was concerned... it is no heavier than other rifles of its day. Look at the Mauser M1898, the U.S. M1917, the Mosin Nagant M1891, the Lebel. All big, long, heavy rifles.
It was accurate enough. The British made many sniper rifles out of Lee Enfields, Ross, and P14 rifles.
If you are silly enough to go into battle with a 30-30 Winchester, or the like, that's up to you. British soldiers were trained to hit a man-sized target at 200 yards, shooting 10 rounds in 15 seconds. That's what the Germans faced at the Battle of the Marne.
I'm willing to bet that German casualties due to Enfield fire of that battle alone were enough to beat the total number of native Americans killed by .45-70 and .30-30 combined. Let's see... the .45-70 went into service around 1874 and was replaced by the .30-40 Krag in the mid 1890s?
Let's guess that German casualites were 250,000. And half of that due to artillery. So we have 125,000. Let's give the French 2/3 because they were the bulk of the Allied defense, and the British Expeditionary Forces were quite small in comparision... leaving us with 41,667 German casualities. British batalions did not have many Vickers machine guns... so I'm willing to guess that the majority of the shots fired were from Lee Enfield rifles.
But let's not loose focus on the discussion...
What makes a rifle great in the list isn't necessary the number of kills or service length, but how it changed the world, the military, the way battles are fought, the quality of the firearm, etc.
The reason you saw SMLEs going for wonderfully low prices, more like $125 to $350 today, for a No.1 MkIII* is because there are so many of them and that these rifles are very well worn, and by American standards... UGLY. These rifles have been described as 2x4s with a pipe stuck in them.
With everything else, jumpingrunt, I tend to agree, especially about the FN FAL in the Six Day War. A great rifle for Europe, or the Falklands, but not for the desert. The Israeli solution: Make a better AK and call it Galil.
Just a few cents more.

- conroy